1. Field of the Invention
The present invention relates to an information processing apparatus, an information processing method, and a program.
2. Description of the Related Art
Nowadays, a receiving apparatus capable of receiving a radio signal transmitted from a satellite is mounted in movable bodies such as automobiles and mobile phones. According to GPS (Global Positioning System) positioning, the position of a moving body in which such a receiving apparatus is mounted can be estimated. Position estimation technology using such a receiving apparatus is an important common fundamental technology in a wide variety of fields such as navigation, security, and entertainment.
Japanese Patent Application Laid-Open No. 2006-171012 discloses a technology in which PHS (Personal Handy System) measures signal intensity of a signal transmitted from a base station and estimates the position of the local machine based on the measured signal intensity. More specifically, a base station of PHS is installed by a communication operator and thus, the installation location thereof is normally known. Therefore, if PHS measures signal intensity of signals transmitted from three base stations or more and estimates the distance between each base station and the local machine based on the measured signal intensity, the position of the local machine can be estimated based on the principle of triangulation in which the installation position of each base station is used as a reference.
Also, a position estimation technology in which an information processing apparatus that performs radio communication with a base station (access point) of wireless LAN (Local Area Network) measures signal intensity of a signal transmitted from the base station and an information management apparatus communicable with the information processing apparatus estimates the position of the information processing apparatus based on the signal intensity can be considered. For example, a base station of wireless LAN transmits a beacon to signal the presence of the base station of the wireless LAN around the base station at fixed periods (for example, 5 times/sec). The information processing apparatus transmits signal intensity of such a beacon to the information management apparatus and the information management apparatus can estimate the position of the information processing apparatus based on the signal intensity and the position of the wireless LAN registered in advance.